我目前正在研究实现图像Gridview的Universal-Image-Loader。我能够使用预定义的图像路径运行项目。请帮助找到更好的解决方案。
基于this：
问题是我想使用保存在我的数据库中的URL字符串集
例如file:///storage/sdcard0/folder/folder/folder/Image.jpg
现在我在活动A ：
中有这个public class LoadMainMenuActivty extends BaseActivity {
private static final String TEST_FILE_NAME = "Universal Image Loader @#&=+-_.,!()~'%20.png";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
new Constants(this.getBaseContext());
setContentView(R.layout.load_main_menu_activity);
File testImageOnSdCard = new File(Environment.getExternalStorageDirectory(), TEST_FILE_NAME);
if (!testImageOnSdCard.exists()) {
copyTestImageToSdCard(testImageOnSdCard);
}
new createFolders().execute();
// Initialize Buttons
Button btnOrderByList = (Button) findViewById(R.id.btnOrder);
// Button Start Application
// btnStartApp = (Button) findViewById(R.id.btnStartApp);
btnOrderByList.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// Perform action on click
// Launch Add New product Activity
Intent i = new Intent(getApplicationContext(),
LoadMainGroupsActivty.class);
// Closing all previous activities
// i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(i);
}
});
}
public void onImageGridClick(View view) {
Log.d("Error", "Here");
Intent intent = new Intent(this, ImageGridActivity.class);
intent.putExtra(Extra.IMAGES, IMAGES);
startActivity(intent);
}
@Override
public void onBackPressed() {
imageLoader.stop();
super.onBackPressed();
}
private void copyTestImageToSdCard(final File testImageOnSdCard) {
new Thread(new Runnable() {
@Override
public void run() {
try {
InputStream is = getAssets().open(TEST_FILE_NAME);
FileOutputStream fos = new FileOutputStream(testImageOnSdCard);
byte[] buffer = new byte[8192];
int read;
try {
while ((read = is.read(buffer)) != -1) {
fos.write(buffer, 0, read);
}
} finally {
fos.flush();
fos.close();
is.close();
}
} catch (IOException e) {
L.w("Can't copy test image onto SD card");
}
}
}).start();
}
/**
* Background Async Task to Load all product by making HTTP Request
* */
class createFolders extends AsyncTask<String, String, String> {
@Override
protected void onPreExecute() {
super.onPreExecute();
}
protected String doInBackground(String... params) {
//Creating folders in SD card
}
}
}
：
public final class Constants {
static DatabaseHandler db = new DatabaseHandler(getContext());
static Context context;
public Constants(Context context)
{
Constants.context = context;
}
static Context getContext()
{
return Constants.context;
}
///public static final List<String> IMAGES = db.getImagePath();
//Not sure with this
static String[] paths = db.getImagePath();
public static final String[] IMAGES = new String[] {
// Heavy images
"file:///storage/sdcard0/folder/folder/folder/image.jpg",
"https://lh4.googleusercontent.com/-K2FMuOozxU0/T3R4lRAiBTI/AAAAAAAAAE8/a3Eh9JvnnzI/s1024/sample_image_02.jpg",
"https://lh5.googleusercontent.com/-SCS5C646rxM/T3R4l7QB6xI/AAAAAAAAAFE/xLcuVv3CUyA/s1024/sample_image_03.jpg",
"https://lh6.googleusercontent.com/-f0NJR6-_Thg/T3R4mNex2wI/AAAAAAAAAFI/45oug4VE8MI/s1024/sample_image_04.jpg",
"https://lh3.googleusercontent.com/-n-xcJmiI0pg/T3R4mkSchHI/AAAAAAAAAFU/EoiNNb7kk3A/s1024/sample_image_05.jpg",
"https://lh3.googleusercontent.com/-X43vAudm7f4/T3R4nGSChJI/AAAAAAAAAFk/3bna6D-2EE8/s1024/sample_image_06.jpg",
"https://lh5.googleusercontent.com/-MpZneqIyjXU/T3R4nuGO1aI/AAAAAAAAAFg/r09OPjLx1ZY/s1024/sample_image_07.jpg",
"https://lh6.googleusercontent.com/-ql3YNfdClJo/T3XvW9apmFI/AAAAAAAAAL4/_6HFDzbahc4/s1024/sample_image_08.jpg",
"https://lh5.googleusercontent.com/-Pxa7eqF4cyc/T3R4oasvPEI/AAAAAAAAAF0/-uYDH92h8LA/s1024/sample_image_09.jpg",
"https://lh4.googleusercontent.com/-Li-rjhFEuaI/T3R4o-VUl4I/AAAAAAAAAF8/5E5XdMnP1oE/s1024/sample_image_10.jpg",
"https://lh5.googleusercontent.com/-_HU4fImgFhA/T3R4pPVIwWI/AAAAAAAAAGA/0RfK_Vkgth4/s1024/sample_image_11.jpg",
"https://lh6.googleusercontent.com/-0gnNrVjwa0Y/T3R4peGYJwI/AAAAAAAAAGU/uX_9wvRPM9I/s1024/sample_image_12.jpg",
"https://lh3.googleusercontent.com/-HBxuzALS_Zs/T3R4qERykaI/AAAAAAAAAGQ/_qQ16FaZ1q0/s1024/sample_image_13.jpg",
"https://lh4.googleusercontent.com/-cKojDrARNjQ/T3R4qfWSGPI/AAAAAAAAAGY/MR5dnbNaPyY/s1024/sample_image_14.jpg",
"https://lh3.googleusercontent.com/-WujkdYfcyZ8/T3R4qrIMGUI/AAAAAAAAAGk/277LIdgvnjg/s1024/sample_image_15.jpg",
"https://lh6.googleusercontent.com/-FMHR7Vy3PgI/T3R4rOXlEKI/AAAAAAAAAGs/VeXrDNDBkaw/s1024/sample_image_16.jpg",
"https://lh4.googleusercontent.com/-mrR0AJyNTH0/T3R4rZs6CuI/AAAAAAAAAG0/UE1wQqCOqLA/s1024/sample_image_17.jpg",
"https://lh6.googleusercontent.com/-z77w0eh3cow/T3R4rnLn05I/AAAAAAAAAG4/BaerfWoNucU/s1024/sample_image_18.jpg",
"https://lh5.googleusercontent.com/-aWVwh1OU5Bk/T3R4sAWw0yI/AAAAAAAAAHE/4_KAvJttFwA/s1024/sample_image_19.jpg",
"https://lh6.googleusercontent.com/-q-js52DMnWQ/T3R4tZhY2sI/AAAAAAAAAHM/A8kjp2Ivdqg/s1024/sample_image_20.jpg",
"https://lh5.googleusercontent.com/-_jIzvvzXKn4/T3R4t7xpdVI/AAAAAAAAAHU/7QC6eZ10jgs/s1024/sample_image_21.jpg",
"https://lh3.googleusercontent.com/-lnGi4IMLpwU/T3R4uCMa7vI/AAAAAAAAAHc/1zgzzz6qTpk/s1024/sample_image_22.jpg",
"https://lh5.googleusercontent.com/-fFCzKjFPsPc/T3R4u0SZPFI/AAAAAAAAAHk/sbgjzrktOK0/s1024/sample_image_23.jpg",
"https://lh4.googleusercontent.com/-8TqoW5gBE_Y/T3R4vBS3NPI/AAAAAAAAAHs/EZYvpNsaNXk/s1024/sample_image_24.jpg",
"https://lh6.googleusercontent.com/-gc4eQ3ySdzs/T3R4vafoA7I/AAAAAAAAAH4/yKii5P6tqDE/s1024/sample_image_25.jpg",
"https://lh5.googleusercontent.com/--NYOPCylU7Q/T3R4vjAiWkI/AAAAAAAAAH8/IPNx5q3ptRA/s1024/sample_image_26.jpg",
"https://lh6.googleusercontent.com/-9IJM8so4vCI/T3R4vwJO2yI/AAAAAAAAAIE/ljlr-cwuqZM/s1024/sample_image_27.jpg",
"https://lh4.googleusercontent.com/-KW6QwOHfhBs/T3R4w0RsQiI/AAAAAAAAAIM/uEFLVgHPFCk/s1024/sample_image_28.jpg",
"https://lh4.googleusercontent.com/-z2557Ec1ctY/T3R4x3QA2hI/AAAAAAAAAIk/9-GzPL1lTWE/s1024/sample_image_29.jpg",
"https://lh5.googleusercontent.com/-LaKXAn4Kr1c/T3R4yc5b4lI/AAAAAAAAAIY/fMgcOVQfmD0/s1024/sample_image_30.jpg",
"https://lh4.googleusercontent.com/-F9LRToJoQdo/T3R4yrLtyQI/AAAAAAAAAIg/ri9uUCWuRmo/s1024/sample_image_31.jpg",
"https://lh4.googleusercontent.com/-6X-xBwP-QpI/T3R4zGVboII/AAAAAAAAAIs/zYH4PjjngY0/s1024/sample_image_32.jpg",
"https://lh5.googleusercontent.com/-VdLRjbW4LAs/T3R4zXu3gUI/AAAAAAAAAIw/9aFp9t7mCPg/s1024/sample_image_33.jpg",
"https://lh6.googleusercontent.com/-gL6R17_fDJU/T3R4zpIXGjI/AAAAAAAAAI8/Q2Vjx-L9X20/s1024/sample_image_34.jpg",
"https://lh3.googleusercontent.com/-1fGH4YJXEzo/T3R40Y1B7KI/AAAAAAAAAJE/MnTsa77g-nk/s1024/sample_image_35.jpg",
"https://lh4.googleusercontent.com/-Ql0jHSrea-A/T3R403mUfFI/AAAAAAAAAJM/qzI4SkcH9tY/s1024/sample_image_36.jpg",
"https://lh5.googleusercontent.com/-BL5FIBR_tzI/T3R41DA0AKI/AAAAAAAAAJk/GZfeeb-SLM0/s1024/sample_image_37.jpg",
"https://lh4.googleusercontent.com/-wF2Vc9YDutw/T3R41fR2BCI/AAAAAAAAAJc/JdU1sHdMRAk/s1024/sample_image_38.jpg",
"https://lh6.googleusercontent.com/-ZWHiPehwjTI/T3R41zuaKCI/AAAAAAAAAJg/hR3QJ1v3REg/s1024/sample_image_39.jpg",
// Light images
"http://tabletpcssource.com/wp-content/uploads/2011/05/android-logo.png",
"http://simpozia.com/pages/images/stories/windows-icon.png",
"https://si0.twimg.com/profile_images/1135218951/gmail_profile_icon3_normal.png",
"http://www.krify.net/wp-content/uploads/2011/09/Macromedia_Flash_dock_icon.png",
"http://radiotray.sourceforge.net/radio.png",
"http://www.bandwidthblog.com/wp-content/uploads/2011/11/twitter-logo.png",
"http://weloveicons.s3.amazonaws.com/icons/100907_itunes1.png",
"http://weloveicons.s3.amazonaws.com/icons/100929_applications.png",
"http://www.idyllicmusic.com/index_files/get_apple-iphone.png",
"http://www.frenchrevolutionfood.com/wp-content/uploads/2009/04/Twitter-Bird.png",
"http://3.bp.blogspot.com/-ka5MiRGJ_S4/TdD9OoF6bmI/AAAAAAAAE8k/7ydKtptUtSg/s1600/Google_Sky%2BMaps_Android.png",
"http://www.desiredsoft.com/images/icon_webhosting.png",
"http://goodereader.com/apps/wp-content/uploads/downloads/thumbnails/2012/01/hi-256-0-99dda8c730196ab93c67f0659d5b8489abdeb977.png",
"http://1.bp.blogspot.com/-mlaJ4p_3rBU/TdD9OWxN8II/AAAAAAAAE8U/xyynWwr3_4Q/s1600/antivitus_free.png",
"http://cdn3.iconfinder.com/data/icons/transformers/computer.png",
"http://cdn.geekwire.com/wp-content/uploads/2011/04/firefox.png?7794fe",
"https://ssl.gstatic.com/android/market/com.rovio.angrybirdsseasons/hi-256-9-347dae230614238a639d21508ae492302340b2ba",
"http://androidblaze.com/wp-content/uploads/2011/12/tablet-pc-256x256.jpg",
"http://www.theblaze.com/wp-content/uploads/2011/08/Apple.png",
"http://1.bp.blogspot.com/-y-HQwQ4Kuu0/TdD9_iKIY7I/AAAAAAAAE88/3G4xiclDZD0/s1600/Twitter_Android.png",
"http://3.bp.blogspot.com/-nAf4IMJGpc8/TdD9OGNUHHI/AAAAAAAAE8E/VM9yU_lIgZ4/s1600/Adobe%2BReader_Android.png",
"http://cdn.geekwire.com/wp-content/uploads/2011/05/oovoo-android.png?7794fe",
"http://icons.iconarchive.com/icons/kocco/ndroid/128/android-market-2-icon.png",
"http://thecustomizewindows.com/wp-content/uploads/2011/11/Nicest-Android-Live-Wallpapers.png",
"http://c.wrzuta.pl/wm16596/a32f1a47002ab3a949afeb4f",
"http://macprovid.vo.llnwd.net/o43/hub/media/1090/6882/01_headline_Muse.jpg",
// Special cases
"http://cdn.urbanislandz.com/wp-content/uploads/2011/10/MMSposter-large.jpg", // very large image
"file:///sdcard/Universal Image Loader @#&=+-_.,!()~'%20.png", // Image from SD card with encoded symbols
"assets://Living Things @#&=+-_.,!()~'%20.jpg", // Image from assets
"drawable://" + R.drawable.ic_launcher, // Image from drawables
"http://upload.wikimedia.org/wikipedia/ru/b/b6/Как_кот_Ñ?_мышами_воевал.png", // Link with UTF-8
"https://www.eff.org/sites/default/files/chrome150_0.jpg", // Image from HTTPS
"http://bit.ly/soBiXr", // Redirect link
"http://img001.us.expono.com/100001/100001-1bc30-2d736f_m.jpg", // EXIF
"", // Empty link
"http://wrong.site.com/corruptedLink", // Wrong link
};
public static class Config {
public static final boolean DEVELOPER_MODE = false;
}
public static class Extra {
public static final String IMAGES = "com.nostra13.example.universalimageloader.IMAGES";
public static final String IMAGE_POSITION = "com.nostra13.example.universalimageloader.IMAGE_POSITION";
}
}
ImageGridActivity：
public class ImageGridActivity extends AbsListViewBaseActivity {
String[] imageUrls;
DisplayImageOptions options;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.ac_image_grid);
Bundle bundle = getIntent().getExtras();
imageUrls = bundle.getStringArray(Extra.IMAGES);
options = new DisplayImageOptions.Builder()
.showStubImage(R.drawable.ic_stub)
.showImageForEmptyUri(R.drawable.ic_empty)
.showImageOnFail(R.drawable.ic_error)
.cacheInMemory(true)
.cacheOnDisc(true)
.bitmapConfig(Bitmap.Config.RGB_565)
.build();
listView = (GridView) findViewById(R.id.gridview);
((GridView) listView).setAdapter(new ImageAdapter());
listView.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
startImagePagerActivity(position);
}
});
}
private void startImagePagerActivity(int position) {
Intent intent = new Intent(this, ImageGridActivity.class);
intent.putExtra(Extra.IMAGES, imageUrls);
intent.putExtra(Extra.IMAGE_POSITION, position);
startActivity(intent);
}
public class ImageAdapter extends BaseAdapter {
@Override
public int getCount() {
return imageUrls.length;
}
@Override
public Object getItem(int position) {
return null;
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
final ImageView imageView;
if (convertView == null) {
imageView = (ImageView) getLayoutInflater().inflate(R.layout.item_grid_image, parent, false);
} else {
imageView = (ImageView) convertView;
}
imageLoader.displayImage(imageUrls[position], imageView, options);
return imageView;
}
}
}
数据库处理器：
@SuppressWarnings("null")
public String[] getImagePath()
{
String [] paths = null;
String selectQuery = "SELECT * FROM " + TABLE_PATH;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
int i = 1;
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
paths[i] = cursor.getString(0).toString();
Log.d("getPathImage:", cursor.getString(0).toString());
i++;
} while (cursor.moveToNext());
}
return paths;
}
老实说，我不知道如何将数据库中返回的图像分配到IMAGES
public static final String[] IMAGES = new String[] {
"file:///storage/sdcard0/folder/folder/folder/Image.jpg",};
答案 0 :(得分：1)
public List<String> getImagePath()
{
ArrayList<String> paths = new ArrayList<String>();
String selectQuery = "SELECT * FROM " + TABLE_PATH;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
paths.add(cursor.getString(0).toString());
Log.d("getPathImage:", cursor.getString(0).toString());
} while (cursor.moveToNext());
}
return paths;
}
然后
DBHandler db = new DBHandler(ActivityName.this);
db.open();
ArrayList<String> list = getImagePath();
现在，您可以使用适配器类中的列表，并使用它来使用Universal Image loader显示图像。
侧面注释您可以从SD卡获取图像路径并使用UIL显示图像。所以你不需要数据库来实现这个目的。
更多关于如何使用UIL。
获取路径后
ListView lv =(ListView) findViewById(R.id.listView);
LazyAdapter adapter = new LazyAdapter(ActivityName.this,list);
lv.setAdapter(adapter);
LazyAdaper
public class LazyAdapter extends BaseAdapter {
private Activity activity;
private ArrayList path;
private LayoutInflater inflater=null;
public ImageLoader imageLoader;
DisplayImageOptions options;
public LazyAdapter(Activity a, ArrayList<String> paths) {
activity = a;
path = paths;
inflater = (LayoutInflater)activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
File cacheDir = StorageUtils.getOwnCacheDirectory(a, "MyFolderCache");
// Get singletone instance of ImageLoader
imageLoader = ImageLoader.getInstance();
// Create configuration for ImageLoader (all options are optional)
ImageLoaderConfiguration config = new ImageLoaderConfiguration.Builder(a)
// You can pass your own memory cache implementation
.discCacheExtraOptions(1024, 1024, CompressFormat.PNG, 100)
.discCache(new UnlimitedDiscCache(cacheDir)) // You can pass your own disc cache implementation
.discCacheFileNameGenerator(new HashCodeFileNameGenerator())
.enableLogging()
.build();
// Initialize ImageLoader with created configuration. Do it once.
imageLoader.init(config);
//imageLoader.init(ImageLoaderConfiguration.createDefault(a));
// imageLoader=new ImageLoader(activity.getApplicationContext());
options = new DisplayImageOptions.Builder()
.showStubImage(R.drawable.ic_launcher)
.cacheInMemory()
.cacheOnDisc()
.displayer(new RoundedBitmapDisplayer(20))
.build();
}
public int getCount() {
return path.size();
}
public Object getItem(int position) {
return position;
}
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
View vi=convertView;
ViewHolder vh = new ViewHolder();;
if(convertView==null)
{
vi = inflater.inflate(R.layout.row, null);
vh.iv=(ImageView)vi.findViewById(R.id.ivv);
vh.pb= (ProgressBar)vi.findViewById(R.id.pb);
vh.tv = (TextView) vi.findViewById(R.id.textView1);
vh.tv1= (TextView) vi.findViewById(R.id.textView2);
}
vh.tv.setText("Image in postion =");
vh.tv1.setText(""+position);
display(vh.iv, data[position], vh.pb);
//imageLoader.displayImage(path.get(position).toString(), image,options);
return vi;
}
public void display(ImageView img, String url, final ProgressBar spinner)
{
imageLoader.displayImage(url, img, options, new ImageLoadingListener() {
@Override
public void onLoadingStarted(String imageUri, View view) {
spinner.setVisibility(View.VISIBLE);
}
@Override
public void onLoadingFailed(String imageUri, View view, FailReason failReason) {
spinner.setVisibility(View.GONE);
}
@Override
public void onLoadingComplete(String imageUri, View view, Bitmap loadedImage) {
spinner.setVisibility(View.GONE);
}
@Override
public void onLoadingCancelled(String imageUri, View view) {
}
});
}
public static class ViewHolder
{
ImageView iv;
TextView tv,tv1;
ProgressBar pb;
}
}
row.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<ImageView
android:id="@+id/imageView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:src="@drawable/ic_launcher" />
<ProgressBar
android:id="@+id/pb"
android:layout_centerInParent="true"
android:layout_gravity="center"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_above="@+id/textView2"
android:layout_alignParentLeft="true"
android:layout_marginBottom="21dp"
android:layout_marginLeft="31dp"
android:text="TextView" />
<TextView
android:id="@+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="@+id/textView1"
android:layout_alignParentBottom="true"
android:text="TextView" />
</RelativeLayout>
你查了一个UIL的例子@ Caching images and displaying
要从SD卡获取图像，请考虑您的文件夹包含图像。
private File[] listFile;
ArrayList<String> f = new ArrayList<String>();
public void getFromSdcard()
{
File file = new File(android.os.Environment.getExternalStorageDirectory(),"MyFolder");
if (file.isDirectory())
{
listFile = file.listFiles();
for (int i = 0; i < listFile.length; i++)
{
f.add(listFile[i].getAbsolutePath());
}
}
}
答案 1 :(得分：1)
只需在if之后替换DatabaseHandler中的Cursor cursor = db.rawQuery(selectQuery, null);条款，如下所示：
cursor.moveToFirst();
while (cursor.isAfterLast() == false) {
List<String> list = new ArrayList<String>();
list.add(cursor.getString(0).toString());
cursor.moveToNext();
}
String[] paths = list.toArray(new String[list .size()]);
return paths;
答案 2 :(得分：0)
你不能这样做：
String [] paths = null;
然后这个：
paths[i] = cursor.getString(0).toString(); // i is 0 initially
这将抛出ArrayIndexOutOfBoundsException。
您可以使用List<String>代替String[]。{1}}。使用List<String>方法将每个元素添加到add()。
List<String> pathList = new ArrayList<String>();
pathList.add(cursor.getString(0));
然后从方法返回一个数组：
return pathList.toArray(new String[pathList.size()]);